Filling head for vacuum powder filling machines



C. F. CARTER June 16, 1953 FILLING HEAD FOR VACUUM POWDER FILLINGMACHINES Filed April 3, 1952 All? 39 NQZ/IEAD GENTRAL HEAD No.1 HEAD AIRINVENTOR. ClaremeE Carhr 3 0W um um ATTORNEYS Patented June 16, 1953UNITED STATES m-E "IOF-FICEJ;

FILLING HEAD FOR VACUUM POWDER FILLING MACHINES Clarence F. Carter,Danville, Ill. u 1 Application April 3, 1952, Serial N 0. 280,290 I Thisinvention relates to a vacuum filling head and shroud useful for fillingcontainers, particularly flexible or non-rigid containers such as bags,cardboard boxes,;and the like, with powders. The filling head of thisinvention may be used in connection with vacuum filling machines of thetype described in my U. S. Patents Nos. 2,170,469 and 2,443,182, andapplication S. N. 593 filed January 5, 1948, now Patent No. 2,613,864,issued October 14,1952.

It is an object of the invention to provide-a .compact filling headandshroud for use particularly in connection with multiple head powder,filling machines wherein the rate of filling may be of the order ofseveral hundred containers per hour.

Figure 1 is a plan view filling head; and Figure 2 is a sectionalelevation of the head and shroud taken along the line 2+2. I is a hopperwhich may be of the rotary type disclosed in U. S. Patent No. 2,443,182.The filling head proper is generally designated as The hopper I0 isattached to filling head II in partial section of the by means of flange|2, a plate 30 lying therebetween. Through the center of the body H is apowder passageway I3 in which may be disposed a valve of the typedisclosed in my copending application Serial No. 271,748, filed February15,

1952. The Valve comprises a vertical tube l4 centrally located in theannular space l3. The tube I4 is supported on a line |5 which extendsoutwardly through the body of the filling'head and may be connected to asource of air pressure and a source of vacuum. Thus the line l5 may betermed a vacuum-air line. The line may be attached to a three-way valve,one inlet of which is attached to a source of air pressure and the otherto a source of vacuum, or the line may lead to an oscillating valve ofthe type shown in my .copending application, for an oscillating valvefmechanism, filed concurrently herewith. Around the tube I4 is aninflatable rubber tube Hi. This ,is attached at either end. There areperforations ll in tube l4 and tube |6- lies over these. When airpressure is applied through line IS the tube I6 is inflated to theposition shown by the dotted lines, thus effectively closing the passagel3.

, Attached by means of flange l8 to the filling head II is a shroud I9which may have a rubber .skirt intended to coact with a platform 2| toseal the bottom of the shroud. This platform .is pneumatically operatedby means of an air cylinder or. other suitable means for raising acontainer '22 into filling position and lowering it 5 Claims. (01.226-116) out of the shroud when the filling operation is l3 are annularPatent No. 2,170,469. The structure ssociat d .with the annular kerf 23Will be hereinafter referredto as head No. I and that associated withkerf 24 ,will be referred to as head No. 2, as, may be seen in Figure1'. v v V Extendin into the kerf 23 is a'series of vertical passageways29. Similar passageways open into kerf 24. The vertical passageways 29are branches of horizontal main passageway 3|, this passageway beingclosed at the top by plate 30. Relief port 32 opens into main passageway3|, as does vacuum port 33. A second branch passageway 34 leadsdownwardly into the "interior of the shroud, externally of thecontainer. Extending into the filling head is line 35 (or 35') whichopens into passageway 36 and vacuum supply port 31. A valve block 38 issecured tothe filling head II. In the valve block is a rectangularrecess lying over ports 33 and 31. The recess is divided longitudinallyby an inflatable diaphragm 39 of rubberor othersuitable ma from beingdrawn through head No.1 by way of line 35 (or head No. 2 by way of line35'). When vacuum is applied to line 42 (or 52), diaphragm 39 is pulledaway from ports 33 and 3l so that a continuous passageway is formed fromline 35 through port 31, port 33 and passageways 29, 3| and 34, thussimultaneously evacuating the interior of container 22 and the space in.the shroud surrounding container 22. Thus when the valve in passageway|3-is open, powder is withdrawn from hopper l0 into the container. Sincethe pressure inside and outsideof the container is equal, the containercannot burst even though it be a paper bag, cardboard box or the like. 1

The construction and operation of head No. 2 is identical with that ofhead No.

A block 43 is attached to the body of the filling head II and is ofsimilar construction to the control valves of filling heads Nos..l and2.

block 43. The recess is divided longitudinally by a rubber diaphragm46leaving a passageway 4'! between the diaphragm and the body H of thehead. Leading from the passageway 41' is an exitport 48 which opens tothe atmosphere. Thus when air pressure is applied to diaphragm 46through line 44 it closes relie'f'port- 32 and exit port 43 and cuts offcommunication of the atmosphere with theinterior of the container andshroud. When vacuum is drawn through line 44, diaphragm 46 is pulledaway from ports '32 and 48 and there is communication of the interior ofthe shroudand the container with the atmosphere.

The operation of the filling head during the filling operation issimilarto that 'disclosed in my U. S. Patent No. 2,170,469. The operation maybe summarized as follows:

At the beginning of the filling operation the platform 2| has beenlowered away from the shroud and a container is placed theron. Theplatform 2l is then raised, putting th container 22 into fillingposition and sealing it within the shroud. If the container is rigid; orrelatively-so, it may thrust against the rubber gasket 49 to form a sealwhich prevents communication between the interior of the container andthe shroud around it. This seal may be further improved byinfiatinganinflatable member 50 which lies in the upper part of the shroud andwhen inflated thrusts the wall of the container against that portion ofthe filling head (designated as 5 l) which extends downwardly into theopen top of the container. This structure is not shown in detail but maycorrespond to that shown in my U. S. Patent No. 2,513,143. Modificationof the present filling head to embody the features. disclosed in saidpatent will be readily apparent to one skilled in the art. The oneadvantage of this type of sealing mechanism is to hold a container 'inplace firmly and prevent powder from the container being drawn into theshroud surrounding it. Since the container is held in position at apoint below the open top, it prevents the container from being split.This is particularly important in connection with paper bags.

Up to the point'described, air pressure is applied through line 42 offilling head No. i and line 52 of filling head No. 2, thus thrusting thediaphragm 39 over the ports 33 and 3'! and cutting off the vacuum whichwould otherwise be drawn through the two halves of the filling head.Vacuum is drawn through line 44, pulling diaphragm 46 away from ports 32and 48 so that continuous open passageways lead from the interior of thecontainer and of the shroud to the atmosphere. At this time thepassageway 13 is closed by applying air to line 15 and inflating therubber tube [B into the position shown in the dotted lines so that nopowder can fall through the passageway.

When the filling operation begins air pressure is applied to line 44,thus closing off ports 32 and 48. A vacuum is drawn on lines 42 and 52,thus opening ports 3'! and 33 so that vacuum is drawn through lines 35and 35', evacuating the interior of the container and of the shroud tothe same pressure as heretofore explained. The valve in passageway I3 isnow deflated by applying vacuum to line It. The vacuum existing withincontainer 22 causes powder to flow from hopper 10 into the container.The major part of the filling occurs at this stage. Air pressure maythen be applied to lines 42 and 52, closing ports 33 and 31.

-A vacuum is applied to line 44, opening ports 32 and 48. The air fromthe atmosphere rushes back through passageway 47 and. ports 32 to theinterior of the container and of the shroud. The air drawn throughscreens 25 and 26' dislodges particles of powder that may haveaccumulated there during the initial filling operation.

The central head valve (relief valve) is then closed by applying airpressure to line 44. Air pressure is still applied to line 52, thusefiectively closing head No. 2. Head No. l is opened by applying vacuumto line 42, the valve in passageway l3 remaining open. This causesadditional powder to be drawn from hopper ID into the container. HeadNo. l is then closed and the central head valve is opened, thusrestoring the interior of the container and shroud to atmosphericpresports.

. sure. The central head valve is then closed, head ...No. I remainingclosed and head No. 2. is opened by applying vacuum to line 52. Thisagain evacuates the interior of the container and the shroud,

causing additional powder to flow into the container. This operation maybe repeated several times. It has the advantage of not only makingcertain that the container is completely filled with powder, but itexerts a vibrating efiect on the contents of the container, causing itto be de-aerated and to pack down into the container so that thecontents will not settle after the package is sealed. Suchan'oscillating action has been described in my above-mentioned U. S.patents. A mechanism for producing this oscillating effect is describedin Patent No. 2,538,441.

The invention is not limited to the exact structure of the embodimentillustrated.

I claim as my invention:

1. An apparatus of the character described, comprising a filling headbody, means for attaching the body to a hopper, a shroud mounted on thebody, a powder passageway from the hopper to a container when-in fillingposition, said apparatus including a vacuum-relief system comprising; amain gas passageway in said body, a

first branch passageway connecting the main passageway with the interiorof a container when in filling position, a second branch passagewayconnecting the main passageway with the interior of the shroud externalof the container, an atmospheric relief port opening from'the mainpassageway, a vacuum port opening from said main passageway, a vacuumsupply port in the body adjacent the vacuum port, means for connectingthe vacuum supply port with a source of vacuum, a valve block mounted onthe head covering the vacuum and vacuum supply ports, an inflatablediaphragm in the valve block, and means to infiate and deflate thediaphragm to control the vacuum and vacuum supply ports; and a reliefvalve to control said relief port.

2. The apparatus'of claim 1 further characterized in having aninflatable valve positioned in the powder passageway, and meansattachable to a source of air pressure and a source of vacuum forinflating and deflating said valve.

3. The apparatus of claim 1 further characterized in having a screenedkerf in the body adjacent the powder passageway, said first branchpassageway opening into said kerf. g

4. The apparatus of claim 1 comprising an exit port in the body leadingto the atmosphere, said relief valve comprising a block mounted on thebody over the relief port and the exit port, an inflatable diaphragm insaid block, and means ior inflating and deflating the diaphragm tocontrol the relief and exit ports;

5. The apparatus of claim 1 comprising a first screened kerf extendingpart way around the powder passageway, the first branch passagewayopening into the kerf, a second screen kerf extending part way aroundsaid powder passageway CLARENCE F. CARTER.

No references cited.

